Identification Properties
STREAK
Color of its powder
Does not change
Metallic: as dark as
sample
Nonmetallic: white to
colorless
Streak Plate
Identification Properties
CLEAVAGE
Tendency to split easily
or break along flat
surfaces
Mica 1 direction
FRACTURE
Break on uneven
surfaces
Conchoidal - obsidian
Identification Properties
HARDNESS
Resistance to being
scratched
Mohs’ Scale of
Hardness
Hardness:
resistance of
a mineral to
abrasion
scratching
Mohs’ Scale of
Hardness
Special Identification Properties
Fluorescence
Special Identification Properties
Magnetism
Magnetite
Rocks and the Rock Cycle
“The present is the key to the past”
Geologic processes that happen today
happened in the past
Earth’s present physical features were
formed by these processes
Igneous Rocks
Formed by cooling and
hardening of magma
Plutonic
intrusive
, forms
underground
Volcanic
extrusive
, forms
on surface
2 kinds of magma
High SiO2%, light colored,
thick, slow moving called
acidic
Low SiO2%, dark colored
called mafic
Sedimentary Rock
Form from sediments
hardening into rock
From pieces of other rocks
clastic
, sandstone, shale
Precipitating out of a
solution
chemical
,
limestone, rock salt
From remains of plants and
animals
organic
, coal,
limestone
Metamorphic Rock
“Changed” by heat and pressure
mountain building
Contact with magma
Weathering and the
formation of
sedimentary rocks
Prof. Dr. Ziad Abu-Hamatteh
Faculty of Engineering Technology
Al-Balqa Applied University
Civil Engineering Department
Weathering and the formation
of sedimentary rocks
All materials are susceptible to weathering = interaction between
materials and weather!
Synthetic and natural materials (concrete + minerals and rocks,
iron rods etc.)
Minerals and rocks that form at high P and T (below or above
Earth’s Surface) are unstable on the Surface of the Earth.
They change until they achieve equilibrium with the new
conditions.
Weathering processes are broadly divided into mechanical and
chemical weathering.
Place of Formation
Temperature
cold
hot
shallow
deep
metamorphic
igneous
sedimentary
700 C
30 miles
P
r
e
s
s
u
r
e
Sedimentary rock forming processes
W
T
D
L